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61.
ObjectivesThe aim of this study was to investigate sex differences in the prevalence, extent, and association of coronary artery calcium (CAC) and thoracic aorta calcium (TAC) scores with cardiovascular mortality in a population eligible for lung screening.BackgroundCAC and TAC scores derived from chest computed tomography (CT) might be useful biomarkers for individualized cardiovascular disease prevention and could be especially relevant in high-risk populations such as heavy smokers. Therefore, it is important to know the prevalence of arterial calcifications in male and female heavy smokers, and if there are differences in the predictive value calcifications carry.MethodsWe performed a nested case–control study with 5,718 participants of the CT arm of the NLST (National Lung Screening Trial). Prevalence and extent of CAC and TAC were resampled to the full cohort to provide unbiased estimates of the typical calcium burden of male and female heavy smokers. Weighted Cox proportional hazards regression was used to assess differences in the association of CAC and TAC scores with all-cause and cardiovascular mortality.ResultsCAC was substantially more common and more severe in men (prevalence: 81% vs. 60%; median volume: 104 mm³ vs. 12 mm³). Women had CAC comparable to that of men who were 10 years younger. TAC was equally common in men and women, with a tendency to be more pronounced in women (prevalence: 92% vs. 93%; median volume: 388 mm³ vs. 404 mm³). Both types of calcification were associated with increased cardiovascular and all-cause mortality. TAC scores improved the prediction of coronary heart disease mortality over CAC in men, but not in women. In both sexes, TAC, but not CAC, was associated with cardiovascular mortality other than coronary heart disease.ConclusionsCAC develops later in women, whereas TAC develops equally in both sexes. CAC is strongly associated with coronary heart disease, whereas TAC is especially associated with extracardiac vascular mortality in either sex.  相似文献   
62.

Background

The diagnosis of chronic obstructive pulmonary disease (COPD) in patients with systolic heart failure (SHF) is challenging because symptoms of both conditions overlap. We aimed to estimate the prevalence, correlates and prognostic impact of true COPD in patients with SHF.

Methods

To diagnose COPD under stable conditions according to the guidelines, pulmonary function testing (PFT) was performed in 619 patients six months after hospitalization for congestive SHF. In 272 patients, PFT had been also performed prior to discharge.

Results

In the total cohort, COPD was reported in 23% (144/619). PFT under stable conditions revealed that COPD was absent in 73% (449/619), unconfirmed in 18% (112/619), and proven in 9% (58/619). In 272 patients with serial PFT, initial airway obstruction was found in 19% (51/272) but had resolved in 47% of those (24/51) after six months. Initial hyperinflation detected by bodyplethysmography strongly predicted proven COPD six months later: odds ratio for elevated intrathoracic gas volume 12.8, 95% confidence interval (CI) 2.5–65.9; p = 0.002.After a median follow-up of 34 months, 27% of the total cohort (165/619) had died. Only proven COPD was associated with an increased mortality risk after adjustment for age, sex, NYHA functional class, ejection fraction, atrial fibrillation, smoking, renal dysfunction and diabetes: hazard ratio 1.64, 95%CI 1.03–2.63; p = 0.039.

Conclusions

Airway obstruction is a dynamic phenomenon in SHF. Therefore, a valid diagnosis of COPD in SHF demands serial PFT under stable conditions with special attention to hyperinflation. COPD proven by PFT is associated with an increased all-cause mortality risk.  相似文献   
63.
Executive function in adolescents with ADHD   总被引:1,自引:0,他引:1  
OBJECTIVE: The aim of this study was to clarify executive function weakness in attention-deficit/hyperactivity disorder (ADHD) during adolescence and determine the specificity of executive function weakness to ADHD symptom domains. METHOD: A total of 182 adolescents (105 boys), ages 13 to 17 years, completed a multistage diagnostic assessment; 85 were diagnosed with ADHD: 43 primarily Inattentive type (ADHD-PI) and 42 Combined type (ADHD-C). Participants completed the Stop, Trail Making, Wisconsin Card Sort, and Stroop tasks. RESULTS: The ADHD group exhibited impaired performance compared with the non-ADHD group on executive function measures (multivariate p < .05); there were no ADHD subtype differences. A composite executive function factor was significantly related to inattentive but not hyperactive-impulsive symptoms. CONCLUSIONS: Executive function weakness in adolescent ADHD is specifically related to symptoms of inattention-disorganization. Results are congruent with a dual-pathway model of ADHD cognitive mechanisms.  相似文献   
64.
Epithelioid hemangioendothelioma (EHE) is a rare, vascular sarcoma. Visceral forms arise in the liver/ lungs. We review the clinical and molecular phenotype of pediatric visceral EHE based on the case of a 9‐year‐old male child with EHE of the liver/lungs. His tumor expressed the EHE‐specific fusion oncogene WWTR1‐CAMTA1. Molecular characterization revealed a low somatic mutation rate and activated interferon signaling, angiogenesis regulation, and blood vessel remodeling. After polychemotherapy and resection of lung tumors, residual disease remained stable on oral lenalidomide. Literature review identified another 24 children with EHE of the liver/lungs. Most presented with multifocal, systemic disease. Only those who underwent complete resection achieved complete remission. Four children experienced rapid progression and died. In six children, disease remained stable for years without therapy. Two patients died from progressive EHE 21 and 24 years after first diagnosis. Natural evolution of pediatric visceral EHE is variable, and long‐term prognosis remains unclear.  相似文献   
65.
BACKGROUND: Results from studies in serotonin-1A (5-HT1A) knockout mice and previous positron emission tomography (PET) studies in humans imply a role for 5-HT1A receptors in normal state anxiety as well as in certain anxiety disorders. The objective of this study was to investigate 5-HT1A receptor binding potential (BP) in social anxiety disorder (SAD). METHODS: Using PET and [carbonyl-11C]WAY-100635, we compared a homogeneous group of 12 unmedicated, male SAD patients with 18 healthy control subjects (HC). A multivariate ANOVA with all regional BP values as dependent variables, age and four radiochemical variables as covariates was performed. RESULTS: We found a significantly lower 5-HT1A BP in several limbic and paralimbic areas but not in the hippocampus (p = .234) of SAD patients. The difference in 5-HT1A binding was most significant in the amygdala (-21.4%; p = .003). There was also a more than 20% lower 5-HT(1A) BP of SAD patients in the anterior cingulate cortex (p = .004), insula (p = .003), and dorsal raphe nuclei (p = .030). CONCLUSIONS: The lower 5-HT1A binding in the amygdala and mesiofrontal areas of SAD patients is consistent with 1) preclinical findings of elevated anxiety in 5-HT1A knockout mice, 2) a previous PET study in healthy volunteers showing an inverse correlation between 5-HT1A BP and state anxiety, and 3) another human PET study in patients with panic disorder showing reduced 5-HT1A binding, thus corroborating the potential validity of 5-HT1A receptors as targets in the treatment of human anxiety disorders.  相似文献   
66.
67.
Eleven cis-clerodane diterpenes, seven labdane type diterpenes and one triterpene isolated from Cistus monspeliensis and the resin Ladano of Cistus creticus subsp. creticus were evaluated against Leishmania donovani promastigotes, the causative agent for visceral leishmaniasis. In addition, eleven semisynthetic manoyl oxide, seventeen labdane type derivatives and a triterpene were also evaluated for their antileishmanial activity. 18-Acetoxy-cis-clerod-3-en-15-ol, 15,18-diacetoxy-cis-clerod-3-ene and 13-(E)-8a-hydroxylabd-13-en-15-ol 2-chloroethylcarbamate exhibited the most potent and selective leishmanicidal activity with IC50 values of 3.3 microg/ml, 3.4 microg/ml and 3.5 microg/ml, respectively.  相似文献   
68.
69.
Background and aims Occurrence of tumor relapse is frequent in patients with pancreatic cancer despite the absence of residual tumor detectable at primary surgery and in histopathological examination. Therefore, it has to be assumed that current tumor staging procedures fail to identify minimal amounts of disseminated tumor cells, which might be precursors of subsequent metastatic relapse. The aim of this study was to assess the prognostic impact of minimal tumor cell spread detected in lymph nodes classified as “tumor-free” in routine histopathologic evaluation. Materials and methods A total of 154 “tumor-free” lymph nodes from 59 patients with pancreatic cancer who underwent intentionally curative tumor resection were examined by immunohistochemistry for disseminated tumor cells. Results Fifty (32.5%) of the “tumor-free” lymph nodes obtained from 36 (61%) patients displayed disseminated tumor cells. Multivariate survival analysis revealed that the presence of disseminated tumor cells in “tumor-free” lymph nodes is an independent prognostic factor for both a significantly reduced relapse-free survival (p = 0.03) and overall survival (p = 0.02). Conclusions The frequent occurrence and prognostic impact of immunohistochemically identifiable disseminated tumor cells in lymph nodes of patients with operable pancreatic cancer supports the need for a refined staging system of excised lymph nodes, which should include immunohistochemical examination.  相似文献   
70.
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